Fisher and Shapiro LLC, one of the top three law firms used by mortgage servicers to handle their local foreclosure actions, reported to the court that, in a breach of protocol, affidavits in the cases were changed. Among other things, fees were added after the documents were signed by servicers.

As a result, Moshe Jacobius, presiding judge of the Circuit Court's Chancery Division, has stayed the cases. The delay will not necessarily prevent delinquent borrowers in Cook County from losing their homes to foreclosure, but it likely will give some homeowners time to seek assistance or to make arrangements to live elsewhere.

Instances of sloppy paperwork and improper foreclosure procedures by mortgage servicers and their law firms have rocked the lending industry, which has been overwhelmed by the number of cases. There have been instances of lenders and lawyers signing foreclosure affidavits without reviewing the documents for accuracy, a legal violation that has come to be known as robo-signing.

Accusations of shoddy foreclosure procedures have sparked investigations by all 50 attorneys general and individual state agencies into mortgage servicers' and attorneys' back-office procedures.

The admission to the court by Fisher and Shapiro does not involve rubber-stamping of documents but rather removing the signature page, altering the affidavit's content and reattaching the signature page, the court said.

The changed contents included the addition of attorneys' fees, insurance costs, preservation costs, inspection costs and taxes on the property, costs that may have been incurred before or after the servicer signed the original affidavit, Jacobius said in his order dated March 2.

The firm's admission signals a note of caution to purchasers of distressed homes, which represent about 50 percent of local home sales, because of potential lingering legal issues if the title transfer process was faulty. .

It's uncertain why the documents were altered or who ultimately bears responsibility. It's also unclear whether affected homeowners and servicers, as well as housing counselors, are aware of the court's decision: As of Friday, some were not.